The most common method of installing a submersible mixer is to lower it along a guide which is turnably supported, at least at its lower end, in the tank bottom and has its upper end at the rim or at an opening in the tank cover. These mixers are normally of the propeller type having a horizontal axis and functionally corresponding with side installed propeller mixers. This type of mixer has been used for a long time within the pulp industry for mixing large volumes.
A submersible mixer exerts a significant reaction force against the guide and also, depending on its alternation, a torque around the impeller axis which must be absorbed both by the guide and its attachments. The latter must be installed in an empty tank which sometimes means significant costs. It may also be unadvisable to attach a support bearing to the tank wall or to the bottom since then there is a risk that the wall surface may be damaged. In addition, such a support bearing may collect rags and other objects that may be present in the liquid.